The British government on Monday announced sanctions on 30 ships that it says are part of Russia’s “shadow fleet”, taking to 73 the number of vessels under restrictions by London.

Foreign Secretary David Lammy called the measures the UK’s “biggest sanctions package” yet against tankers and cargo ships used by Moscow to circumvent export and oil embargoes to fund its war against Ukraine.

The UK also sanctioned two Russian insurers it accused of enabling the so-called ghost fleet, which operates under dubious ownership or without proper insurance.

The vessels, often carrying Russian oil and gasoline but flying the flag of another country, allow the Kremlin to keep exporting despite sanctions on exports and an oil price cap on its global sales.

Half of the ships hit by the latest sanctions transported more than $4.3 billion worth of oil and oil products in the last year, according to a Foreign Commonwealth and Development Office (FCDO) statement.

Announced by Lammy during a meeting of G7 foreign ministers in Italy, the new restrictions surpass the number of ships currently targeted by the United States (39) and the European Union (19).

According to London, the sanctions “are working” with “Russia becoming increasingly reliant on states like North Korea and Iran for military hardware”.

The FCDO noted that two oil tankers, Artemis, which flies under the flag of Gabon, and Sea Fidelity, flagged out of Honduras, had been “idling uselessly in the Baltic Sea after being sanctioned last month”.